This invention relates to a power drivable chuck, and particularly relates to a power drivable chuck having a triangular shank-receiving bore, and to an accessory having a triangular shank for assembly with the chuck.
In the past, chucks have been designed to receive shanks of various cross sections. Such cross sections generally have included hexagonal and round configurations. The manufacture of chucks which accommodate hexagonal shanks is a somewhat costly effort considering that a bore of the chuck is typically machined with five walls. Other wall configurations also have been designed which accommodate a hexagonal shank as well as other shank configurations. However, such other wall configurations are complex and also costly to manufacture.
Thus, there is a need for a chuck which is economical and relatively easy to manufacture, while also providing facility for receipt of shanks of different configurations.
In addition, there is a need for an accessory, such as, for example, a drill bit, having a shank which is economical and easy to manufacture, which can be accommodated by the above-noted economical and easy-to-manufacture chuck.
In some chucks, a locking element, such as, for example, a ball, has a biasing force applied directly thereto, for urging the locking element into a position to lock a shank within a bore of the chuck. With the constant direct application of the biasing force upon the locking element, a loss of structural integrity could result, which could have a undesirable effect upon the operation of the locking feature of the chuck.
Thus, there is a need for a providing a locking element within a chuck which is not subject to a directly applied biasing force.
It is, therefore, an object of this invention to provide a chuck which is economical and relatively easier to manufacture, while also providing facility for receipt of shanks of different configurations.
Another object of this invention is to provide a shank which is economical and easier to manufacture.
Still another object of this invention is to provide a chuck having a locking element which is not subject to a directly applied biasing force.
With these and other objects in mind, this invention contemplates a power drivable chuck for receiving and clamping a shank having a cross section selected from the group consisting of a triangular cross section configuration and a hexagonal cross section configuration. The chuck includes a body having a front face and a shank-receiving bore formed in the front face of the body and extending into the body from the front face. The bore is formed with three angularly interfacing surfaces arranged to drivingly engage the shank. Means are provided for locking the shank with the chuck.
This invention further contemplates a power drivable chuck for receiving and clamping a shank, and includes a body having a shank-receiving bore formed therein and an exterior surface. A passage is formed in the body and extends from the exterior surface to the bore. A locking element is movable within the passage and has a portion thereof which is extendable into the bore. An extension element is assembled with and extends from the locking element. Means are provided for normally urging the extension element, and thereby the locking element, into a position whereby the portion of the locking element extends normally into the bore.
This invention also contemplates an accessory which includes a shank formed in a triangular cross section.
Other objects, features and advantages of the present invention will become more fully apparent from the following detailed description of the preferred embodiment, the appended claims and the accompanying drawings.